Last month, after publishing my interview with NASA's Steve Collins, I promised a second interview with another member of the JPL Curiosity Rover team. Today, we finally get that interview with Erisa Hines, a key member of the JPL team that landed the rover on Mars.

If you’ve been living under a rock the past couple months, here’s the quick recap: Late last November, Curiosity was set off on an 8 1/2-month, 354 million-mile journey to Mars. She’s the largest rover ever sent to the Red Planet, about the size of a Mini Cooper, plutonium powered and packed with all kinds of goodies to perform science experiments once landing safely on the surface of Mars.

On August 5th (Pacific Time), she successfully landed after completing the dangerous 7-minute entry, descent and landing which involved busting through the Mars atmosphere at about 13,000 MPH, a ginormous parachute to help slow it down and some down-firing booster rockets to bring the rover finally to a soft, safe landing.

Erisa Hines was integral member of the team that flew the spacecraft to Mars and was super generous with her time as she gave the following interview over the course of about an hour when I visited JPL a couple months ago.

Name: Erisa HinesBorn and raised: Northeast of Kansas City, MOGrew up: On a farm with ponds to fish in and a horse Collected: She-Ra: Princess of Power dollsSelf-confessed: TomboyPassion growing up: Dancing (tap, jazz, ballet mix)At an early age: Taken with NASA shuttle program and wanted to be an astronaut, but also a veterinarian High School: Valedictorian of graduating classUndergrad: University of Miami (College of Engineering)Grad: MIT (Dual Master in Aerospace & Technology and Policy Program)

DI: While doing your grad studies, were you more interested in building and flying rockets or the science involved?

EH: At the time, definitely building and flying rockets. I didn’t yet have an appreciation for the science. I think it’s been this project (Curiosity rover) and being here through a landing, and seeing the science come back within seconds, whether it’s a picture or starting to hear some of the scientific conversations that are going on about the place we’re in and where the rover is headed, I am now interested in the science.

DI: When you started at JPL, what was your first project?

EH:Dawn, which is the asteroid mission and I appreciate the science they’re doing, which is this really hot, dry rock and this really cold, icy rock, but we think they came from the same place in history, and have evolved very differently. So let’s go study them with the same instruments, get comparative data, and try and learn from that. The science is much more real to me. I worked on this mission for about a year and a half, where I was heavily supporting the flight director at the time. So I was helping to get all the launch products ready. And I was running launch scenarios in the test bed.

DI: So after Dawn, what was next for you on your personal journey to Mars?

EH: I next worked on Altair, the lunar landers missions. So in the ‘60s, those lunar modules held two men and took them to the surface of the moon. With Altair, we were designing the spacecraft to hold 4-6 people, so it was a much larger lander than what had been done before. Had we continued with the program (it was shelved), it would have been the largest spacecraft manned by humans to another planet, or another body. It was based out of the Johnson Space Center in Houston, so I was going to Houston twice a month.

DI: So how’d you get to be part of MSL (Mars Science Lab)?

EH: Well all through the first two projects, I kept telling them that I wanted to do something EDL (Entry, descent, landing), and none of the work I was doing til that point was EDL. MSL’s EDL needed a bit more help with their testing program, so I was talking to Adam Seltzner , the EDL lead, about that particular role. They wanted someone part-time, so I was excited because I knew MSL was such a big deal. There was a part of me that felt it was the wrong time to leave Altair because I was such a key part of the team there. So I gave myself a week to decide. And I waited the whole week, completely stressed-out about it, because my gut was telling me to stay with Altair, even though I wanted the EDL experience. So at the end of the day, I called my mother Friday morning, the day I was supposed to make the decision, and I remember I was crying to her over the phone. Now she knows nothing about the details of these two options, but somehow with mother’s wisdom, ‘cause she’s not an engineer, somehow tells me something that calms me down and I make the decision to stick with Altair. But here’s where it gets interesting: Three to four months later, NASA announces they’re pushing the Curiosity launch back two years, so a bunch of people get let go, and I would have been one of those people. And sure enough, eight months later when they’d gone through enough of a delay and needed to ramp back up on MSL system engineering to get things ready again, I was one of many young, smart engineers who they talked to about filling one of these roles. So they gave me the option of working on the service team or the cruise team and based on the people I knew from cruise and EDL, and that the skillset would be something I could use across other missions, so in October of 2009, I joined the Cruise team. And all of a sudden I was ecstatic! I was suddenly thrown into the fire hose, learning a bunch of stuff that I had no idea how to do. And I got to be a part of the great operations and landing team. So my job officially ended when we landed on Mars, but I’ve now transitioned to...

DI: Wait, wait, wait.... can you talk a little bit about your specific responsibilities during entry, descent and landing?

EH: My team’s job was to make sure the spacecraft was pointed in the right direction -- to keep sun on the solar rays, to keep the antennas pointed at earth, to make corrections to the trajectory along the way by building the commands and executing the commands that fire the thrusters to change the trajectory to get us to the right place at the right time. If we don’t nail that entry corridor, EDL will fail. Most of our work happened on the 8 ½ months on the way to Mars. And then during EDL we help tell that team when to pop the parachute or when to fire thrusters. Now before we launch, our job was to make sure all the pieces of hardware and software -- the censors that are looking at sun and star data -- the software that’s crunching on all that data -- all of this has to be tested and verified. We also throw the spacecraft through scenarios. What happens if we lose a censor? Or a thruster? Can the system still accomplish what we would command them to do in those fault cases?

DI: How did you feel, emotionally, when this room what bananas after it was apparent that Curiosity had touched down on Mars without a hitch?

EH: EDL went so well that every single piece of data we got said, “This works. Okay, this works. This works.” I mean, I kept waiting for something to go wrong, it was too good to be true. Something’s gotta give. You prepare yourself for the worst. But every single piece of data we got back was... so you just thought well, it’s going to be the next thing. Or the next. So when it lands, you’re overwhelmed. I mean, you saw tears. You saw people jumping in the air like crazy. You just react. I dare compare it to anything I haven’t personally experienced, like having a baby, but I don’t think you can anticipate what it would feel like and the actual emotion is just raw. It is whatever you’re body is capable of expressing at that point and time. So for me it was a big sense of satisfaction, but also relief. It was just raw, like relief I would say. And it wasn’t just that moment -- to go into the press conference, and begin to get the sense of how everyone else is talking about it and all the bloggers, and, well, I didn’t know what a meme was before landing night, I’d never really been on reddit, I was very out-of-touch. I mean, I thought landing was going to be the big deal, but when we got pictures back, a day later, when the pictures are coming down and they’re putting them up on the screen, I was overwhelmed again. You could walk out your backyard if you lived in Mohave and this is what you would see. I mean, I’ve seen pictures from MER, I’ve seen other pictures we’ve taken of things, but it doesn’t matter what you’ve seen before. The pictures the rover has taken of itself, the wheels and, well, it doesn’t look real. It’s hard to believe it’s there.

DI: So now that you’ve successfully flown Curiosity to Mars, what are you working on?

EH: I have transitioned to surface mobility, or driving the rover around Mars -- the actuator, the imaging we take -- where we’re going to drive and how we actually drive to get to places -- We can do blind drives where we just tell the rover to ignore what’s in front of you, we know what we’re doing. So drive 10 meters with a zero heading and then I want you to take a small turn and drive five meters in this direction. Then there’s auto-nav, where you basically give the rover a target and you say Go, and you’ve told the rover certain parameters like how far away you want it to keep objects, which size objects to be afraid of, that sort of thing. But you essentially give it autonomy to make decision like when it needs to go around things. It’s a whole different set of software for me to learn about, like the interactions with the camera modules. Interactions with the RSM, the remote sensing mast, because it has cameras associated with it. So I’m doing all this and interacting with the rover planners and talking strategy, what are we going to do on the way to Glenelg? What are we going to do when we get there? Are we going to be there for a couple months? So I’m interacting with the operations team and the scientists. And it’s fun! On days when I’m doing that, I’m in shorts and a t-shirt and a ballcap because I’m out in the sun in our big Mars yard getting dirty, testing on the Curiosity double and I’m covered in red sticky dirt!